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arXiv · 2401.09222

Local Trajectory Variation Exponent (LTVE) for Visualizing Dynamical Systems

Abstract

The identification and visualization of Lagrangian structures in flows plays a crucial role in the study of dynamic systems and fluid dynamics. The Finite Time Lyapunov Exponent (FTLE) has been widely used for this purpose; however, it only approximates the flow by considering the positions of particles at the initial and final times, ignoring the actual trajectory of the particle. To overcome this limitation, we propose a novel quantity that extends and generalizes the FTLE by incorporating trajectory metrics as a measure of similarity between trajectories. Our proposed method utilizes trajectory metrics to quantify the distance between trajectories, providing a more robust and accurate measure of the LCS. By incorporating trajectory metrics, we can capture the actual path of the particle and account for its behavior over time, resulting in a more comprehensive analysis of the flow. Our approach extends the traditional FTLE approach to include trajectory metrics as a means of capturing the complexity of the flow.

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BibTeXRIS

Yun Chen Tsai, Shingyu Leung. 2024-01-17. Local Trajectory Variation Exponent (LTVE) for Visualizing Dynamical Systems. https://arxiv.org/abs/2401.09222

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